I would dollar cost average if it was half of all the money I ever expected to need and I was after a high stock allocation, ie. if I received $1M and my FIRE number was $2M and my allocation was 90% stocks. $25k I would not bother, or with 50% bond target.
I'm with Andy R, I think your bond % is fine given you look to have at least $500k in real estate investments. You should check to see if there are better bond options for your tax rate: if you have a high state tax maybe a treasury fund is better, or for high federal taxes a muni fund might be better, or if both are high then a state muni fund. Nothing against international bonds, but that is also a slightly unusual choice. You might be better with some other type of bond. Or not. Hard to say.